Astronomy and Astrophysics – Astrophysics
Scientific paper
1997-12-16
Astronomy and Astrophysics
Astrophysics
Accepted for publication in ApJ Letters. 11 pages AASTeX + 2 figures + 1 table; added more processing info, brief comparison t
Scientific paper
10.1086/311223
To test the cooling flow model of early-type galaxies, we obtained a complete magnitude-limited sample of 34 early-type galaxies, observed with the PSPC and HRI on ROSAT. The X-ray to optical distribution of galaxies implies a lower envelope that is consistent with the stellar emission inferred from Cen A. When this stellar component is removed, the gaseous emission is related to the optical luminosity by Lx proportional to L_B^m, where m = 3.0-3.5, significantly steeper than the standard theory (m = 1.7). The dispersion about the correlation is large, with a full range of 30-100 in Lx for a fixed L_B. The X-ray temperature is related to the velocity dispersion temperature as Tx proportional to Tsigma^n, where n = 1.43 +/- 0.21, although for several galaxies, Tx is about twice Tsigma. The excessively hot galaxies are generally the most luminous and are associated with the richest environments. We suggest a model whereby environment influences the X-ray behavior of these galaxies: early-type galaxies attempt to drive partial or total galactic winds, which can be stifled by the pressure of their environment. Stifled winds should lead to hotter and higher luminosity systems, which would occur most commonly in the richest environments, as observed.
Bregman Joel N.
Brown Alex B.
No associations
LandOfFree
X-Ray Emission from Early-Type Galaxies: A Complete Sample Observed by ROSAT does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with X-Ray Emission from Early-Type Galaxies: A Complete Sample Observed by ROSAT, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and X-Ray Emission from Early-Type Galaxies: A Complete Sample Observed by ROSAT will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-156643